Circular knitting machine



Oct. 5, 1965 s. J. HADDAD 3,209,616

CIRCULAR KNITTING MACHINE Filed April 29, 1963 4 Sheets-Sheet l Figni INVENTOR.

SING/HAO I #40040 Oct. 5, 1965 5. J. HADDAD 3,209,616

CIRCULAR KNITTING MACHINE Filed April 29, 1963 4 Sheets-Sheet 2 QNN w an Oct. 5, 1965 Filed April 29, 1963 s. .1. HADDAD 3,209,616

CIRCULAR KNITTING MACHINE 4 Sheets-Sheet 3 INVENTOR.

SALOMAO I #40040 I TTOR/YE YJ Oct. 5, 1965 5. J. HADDAD 3,209,616

CIRCULAR KNITTING MACHINE Filed April 29, 1963 4 Sheets-Sheet 4 Fig.5

Z4 3e 46 1e INVENTOR.

United States Patent "ice 3,209,616 CIRCULAR KNITTING MACHINE Salomao J. Hadriad, Charlotte, N.C., assignor to Carolina Knitting Machine Corporation, a corporation of North Carolina Filed Apr. 29, 1963, Ser. No. 277,413 12 Claims. (Cl. 74626) The present invention relates to a circular knitting machine, and more particularly to improvements in the drive of a circular knitting machine that efficiently utilize drive components in a compact and simple manner to obtain enhanced versatility of operation and reliable positioning of the components during operation.

The improvements of the present invention include a drive connection for a circular knitting machine that not only is operable to connect drive means to the machine but also is alternatively operable as a hand crank. This drive connection may be in addition to the usual drive connections to provide an additional operating speed and can be disposed in the same location as, and as a substitute for, a conventional handle so that no appreciable additional space is necessary to accommodate this connection, and the operator need not reach farther than usual to hand crank the machine as he observes the elements at the knitting head. During operation of the machine through this connection the drive means is retained in proper operating relation thereto by retaining means that prevents shifting of the drive components and thereby avoids inadvertent fluctuation in the operating speed even over extended periods, thus providing reliable control of the operating speed.

The operating speed versatility and reliable control provided by the present invention are especially pertinent in high speed knitting, where the machine must be slowed during certain portions of the knitting cycle in which high speeds cannot be tolerated. The provision of an additional operating speed allows operation during certain of the lowed portions at intermediate speeds that can be efficiently tolerated while allowing other portions to be operated at slower speeds, thus providing more efficient operation and higher production rates, and the positive control of the drive connection avoids inadvertent shifting from one speed to another, which shift- .ing causes more pronounced undesirable effects in high speed operation due to the substantial differences between alternative speeds.

The preferred embodiment of the present invention is incorporated in the drive mechanism of a belt driven circular knitting machine, with the drive connection, that also serves as a hand crank, being in the form of a gear train unit mounted on the end of the main drive shaft in the space normally occupied by a conventional handle. This gear train unit is latched in a fixed operating position for driving the shaft at an optional speed upon connection of the drive belt thereto, and is unlatched for revolution about the shaft as a hand crank. The belt is shiftable into driving connection with the gear train unit by a conventional belt shifter, which is retained in position by a belt shifter latch that is operable to prevent undesirable movement of the belt shifter during extended periods in which the belt shifting mechanism periodically fluctuates and would cause momentary shifting of the belt from the drive connection were it not for the present belt shifter latch.

The foregoing features and advantages of the present invention are explained at further length in the following detailed description based on the accompanying drawings, in which:

FIG. 1 is an elevational view of a portion of a circular knitting machine incorporating the preferred embodiment of the present invention;

3,26%,616 Patented Oct. 5, 1665 FIG. 2 is an enlarged vertical sectional view through the main drive shaft of the circular knitting machine of FIG. 1;

FIG. 3 is an enlarged elevational view, partially in section, of the right end of the machine of FIG. 1;

FIG. 4 is an enlarged end view, partially in section, of the gear train unit included in FIG. 3, shown in a partially revolved position;

FIG. 5 is an enlarged elevational view of the drive mechanism portion of the machine of Fig. 1; and

FIG. 6 is an elevational view of the belt shifter mechanism included in FIG. 5.

The preferred embodiment of the present invention is illustrated herein as incorporated in the drive mechanism of a belt driven circular knitting machine 10, such as a Scott & Williams Model K machine. The portions of the machine other than the drive mechanism are of conventional construction and are illustrated in outline form only.

This machine 10 has the usual knitting head 12 at which knitting components are manipulated to knit circular fab ric in a conventional manner, with the knitting components being driven from a laterally extending main drive shaft 14 through gears 16, and with the manipulation of the components being controlled to perform the various sequential operations of a knitting cycle by a main pattern chain 20.

The main drive shaft 14 is operated by a drive mechanism that incorporates the improvements of the present invention and will now be described in detail. Power to operate'the drive mechanism is obtained from an exterior source, such as a rotating line shaft that drives a connecting drive belt 24), which belt drives pulleys that are concentrically mounted on the shaft 14 and variously connected thereto to provide a selection of operating speeds, with the belt 20 being shiftable from one pulley to another to drive the shaft at a particular selected speed.

The inner pulley 24 is mounted on and fixed to the shouldered hub 26 of a gear 28 that is rotatably mounted on the shaft for rotation of a gear train that includes coaxial intermediate gears 30 and 32 mounted on a shaft (not shown) in back of the main shaft, and which in turn rotate the drive gear 34 fixed to the main shaft 14 to impart rotation to the shaft when the belt is driving the inner pulley 24. This gear train is designed to provide an increase in speed in a ratio of about 1 to 2 for high speed operation of the knitting machine.

The second pulley 36 is fixed on a shouldered sleeve 38 that is keyed to the main drive shaft 14 by key blocks 40 extending from keyways 42 in the end of the main shaft into aligned keyways 44 in the sleeve 38. Thus, this second pulley 36 drives the shaft directly at the same rotational speed as the pulley, which provides an intermediate operating speed.

The third pulley 46 provides a third driving connection for the main drive shaft for driving the machine at an optional third speed not heretofore incorporated in conventional knitting machines of this type. The third pulley 46 is mounted on an annular ball bearing 48 on the sleeve 38 for rotation of this pulley on the sleeve and therefore on the shaft 14. This third pulley 46 has a radial web 50 at the end of the ball bearing 48 that extends to a hub 52 loosely fit on the aforementioned shouldered sleeve 38 for rotation with respect to the shaft 14. The pulley hub 52 is locked in driving relation to the hub 54 of a driven gear 56 of a gear train unit 58, with the hubs 52 and 54 being locked by intermeshing teeth 60. The driven gear 56 is loosely mounted for rotation on the intermediate portion 62 of an elongated hub 64 of the drive gear 66 of the gear train unit 58. The end portion 68 of the hub 64 of the drive gear 66 extends coaxially into the end of the main drive shaft 14 and has fixed thereto the aforementioned key blocks 40 that key the sleeve 38 and the shaft 14 together and also key the drive gear 66 to the main drive shaft for driving of the shaft thereby. The drive gear 66 is retained in keyed disposition with respect to the shaft 14 by a retaining bolt 70 that is threaded in the end of the shaft 14 and extends outwardly through the center of the drive gear 66 to an enlarged head 72 that abuts the drive gear to retain it in place.

The gear train unit 58 that includes the driven gear 56 and the drive gear 66 concentrically mounted on the main drive shaft 14 by the extension of the hub 64 of the drive gear 66, also includes intermediate gears 74 and 76 radially disposed with respect to the main drive shaft 14 on a common idler shaft 78 mounted parallel to the main shaft on ball bearings 80 in the sides 82 and 84 of a housing 86 that encloses the gear train unit 58. The gears of the gear train unit 58 intermesh to transmit rotation of the driven gear 56 by the third pulley 46 to the inner intermediate gear 74, which is fixed to the idler shaft 78 to cause rotation of the outer intermediate gear 76, which is also fixed to the idler shaft, and which drives the drive gear 66 to rotate the main drive shaft 14 through the connection of the drive gear hub 64 to the shaft. This gear train unit 58 provides a speed reduction at a ratio of about 2 to 1 for low speed operation of the machine.

The housing 86 of the gear train unit 58 is supported rotatably with respect to the main drive shaft 14 by an annular ball bearing 88 mounted on an outwardly extending annular shoulder 90 of the drive gear 66 and seated in an aperture in the outer side 84 of the housing, and by an annular collar 92 loosely mounted on the driven gear hub 54 and seated in an aperture in the inner side 82 of the housing 86.

The housing 86 is further provided with a handle portion 94 formed by a radial extension 96 of the inner side 82 that serves as a crank arm and carries a handle 98 at its outer end. This handle 98 incorporates latching means in the form of a spring loaded detent 100 extending through the extension 96 of the housing side 82 and retractable into the handle 98 against the bias of the spring 102 by outward displacement of the gripping portion 104 of the handle 98 to which gripping portion the detent is attached. The detent 100 latches in a hole 106 formed in a vertically disposed latch plate 108 that is flush with housing extention 96 and depends from a bracket 110 fixed to the knitting machine frame.

Latching of the detent 100 in the latch plate 108 holds the housing 86 and the enclosed gear train unit 58 in proper fixed operating position for driving of the main drive shaft 14 through the gear train unit 58 when the drive belt 20 is positioned on the third pulley 46.

Unlatching of the detent 100 from the latch plate 108 allows the housing 86 to be manually revolved about the main drive shaft 14, with the aforementioned rotatable mounting of the housing accommodating this revolving of the housing. When the housing 86 is revolved, it carries with it the idler shaft 78 so that the gear train unit 58 also revolves.

The gears of the gear train unit 58 are locked against rotation with respect to the housing 86 during revolving of the housing by stop means in the form of a locking pawl 112 pivotally mounted in the bottom of the housing below the outer intermediate gear 76. This locking pawl 112 is held by its own weight out of contact with the gear 76 when the gear train unit 58 is latched in its fixed operating position, but when the housing and gear train unit are revolved, and the pawl is raised to about the position of FIG. 4, a weak spring 114, overcomes the reduced effective weight of the now depending pawl to lock it in the teeth of the gear 76 and thereby prevent rotation of the gears of the train. The locked gears will thus revolve with the housing in fixed relation thereto and this revolving will cause the drive gear 66 to rotate the main drive shaft 14 in direct relation to the revolving 4 of the housing 86. As a result, the housing serves as a hand crank for cranking the machine manually.

The locking pawl 112 remains locked in the gear teeth throughout continued revolution of the housing 86 due to the back pressure of the gear on the pawl, and will fall out only when the housing is stopped in a lower position and is backed off slightly to relieve the locking pressure.

This function of the housing 86 as a hand crank eliminates the need for a conventional handle structure, and, as the handle portion 94 of the housing is disposed substantially within the axial extent of the housing, the entire housing can be located in the same space occupied by a conventional handle. Thus, no appreciable increase in space is necessary to accommodate the additional third drive provided by this gear train unit 58. The space occupied by the third pulley 46 is the only additional space required by this structure in comparison with a conventional two speed machine. This conservation of space is important because of the limited spacing between machines in a bank of machines and because during hand cranking the operator is usually watching the manipulation of the elements at the knitting head 12, which requires him to reach from the knitting head to the handle portion 94 to hand crank the machine.

In addition to the three drive pulleys described above, the drive mechanism includes the usual idler pulley 116, which is the outer pulley in the illustrated embodiment. This idler pulley 116 allows the machine to be stopped without stopping the drive belt 20. To accomplish this, the idler pulley 116 is mounted on an annular ball bearing 118 that is seated on the hub 52 of the third pulley 46.

In knitting ladies seamless hosiery with the three speed drive mechanism described above the machine can be operated effectively at substantially high speeds, such as 400 rpm, with slower speeds being available for knitting during portions of the knitting cycle that cannot efficiently tolerate this high speed. The two slower speeds allow knitting of some of these critical portions at an intermediate speed for a faster overall production rate.

For example, the welt, afterwelt, leg and foot portions of ladies hosiery can be knit by drive connection through the inner pulley 24 at 400 rpm; the heel, the toe, the courses after the toe (ravel courses) and the non-knitting courses after the stocking has been pressed-off can be knit by drive connection through the second pulley 36 at an intermediate speed of 200 rpm; and the make-up, the transfer, yarn changes, clutching between reciprocal and circular knitting and the various switching operations can be performed with drive connection through the third pulley 46 and gear train unit 58 at a slow speed of rpm.

Various other speeds and speed ratios may be used to advantage, the above speeds being mentioned only as an example of a typical operating arrangement.

The shifting of the belt 20 from one pulley to another to change the driving connection, and thus change the operating speed, is performed by the aforementioned belt shifter 22, which is slidably mounted on a guide shaft 120. A spring 122 pulls the belt shifter 22 inwardly so that a cam follower lug 124 on the belt shifter is in following engagement with a circular cam 126 on the belt shifter drum 128, with the cam 126 controlling shifting of the belt 20 between the first and second pulleys 24 and 36, respectively, in a conventional manner.

Shifting of the belt shifter 22 to position the belt 20 on the third pulley 46 is accomplished by a conventional shifting mechanism that includes an operating bell crank 130 acting on an extension 132 of the belt shifter 22. This extension is longer than conventional for positioning the belt shifter at the third pulley 46 rather than at the second pulley 36 as in conventional mechanisms where there are only two drive pulleys.

In this conventional shifting mechanism, the operating bell crank 130 is actuated by a catch 134 carried by the bell crank 130 and manipulated into engagement with a notched, periodically reciprocating, operating block 136 by a chain reading lever 138 that is responsive to cams, 140, 142, on the links of the control chain 18.

In a conventional two-speed machine this shifting mechanism operates to shift the belt to the second pulley during short periods, as during switching and yarn change operations, and the belt shifter drum cam 126 operates to shift the belt to the same second pulley during prolonged periods. In the present three-speed embodiment, the shifting mechanism operates to shift the belt to the third pulley during both short and prolonged periods. The short periods are controlled by short chain link cams 140, and the prolonged periods are controlled by long chain link cams 142. These long cams 142 may span more than one periodic reciprocation of the operating block 135, so that while the chain reading lever 138 remains raised the bell crank 130 momentarily retracts when the block 136 reciprocates, which would normally cause a momentary shifting of the belt 20 and an undesirable fluctuation in operating speed. Such speed fluctuations are especially undesirable in a high speed operation where the speed differentials are substantial.

To avoid these speed fluctuations, the present invention includes retaining means that prevent back shifting of the belt 20 as long as the chain reading lever 133 is raised in response to the chain link cam 142. In the illustrated preferred embodiment this retaining means is a belt shifter latch 144 pivotally mounted, as at 146, to the machine frame intermediate the ends of the latch. The latch 144 is generally horizontally disposed, and has a short, lever follower, end 148 bent to extend in contacting relation under the chain reading lever 13S, and a long, latching end 150 extending in belt shifter engaging disposition. Due to the latching end 150 being longer than the follower end 148, the latch 144 tends to pivot from a horizontal disposition so that the follower end remains in following contact with the chain reading lever 138.

The latching end 151) of the latch 144 is provided with belt shifter engaging means at the third pulley position of the belt shifter 22. In the embodiment illustrated, this engaging means is a notch 152 formed in the underside of the latching end 150 and aligned with a lug 154 extending from the belt shifter 22 for engagement of the lug 154 in the notch 152 when the latching end 151 of the latch is lowered. The notch is slightly enlarged with respect to the lug so that the belt shifter 22 will move slightly under the pull of the spring 122 when the bell crank 139 retracts (FIG. 6), and will return when the bell crank 130 again moves into operating position (FIG. This movement is not sufficient to shift the belt 20 from the third pulley 46, but is sufiicient to avoid binding of the lug in the latch when the latch is to be raised.

The latch 144 is disposed so that when the chain reading lever 138 is in its lower inoperative position the latching end 150 of the latch will be raised out of contact with the belt shifter lug 154 and the belt shifter 22 can move freely thereunder between pulleys. When the chain reading lever 138 rises in response to a chain link cam 140 and 142 the follower end 148 of the latch rises and the latching end 150 pivots downward onto the belt shifter lug 154, which moves thereunder until it is aligned with the notch 152, at which time the latching end 150 will drop as the lug is engaged in the notch, and will retain the belt shifter 22 at the third pulley 46 until the chain reading lever 138 again moves down, regardless of subsequent reciprocation of the operating block 136.

The belt shifter latch 144 also has a stop finger 156 at the latching end 150 beyond the notch 152 and aligned with the idler pulley position of the belt shifter 22 for engaging the belt shifter lug 154 to latch the belt shifter 22 when it is moved manually to position the belt 20 on the idler pulley 116. This stop finger 156 is below the level of the notch 152 so that, when the stop finger is engaging the lug, the latch will be pivoted out of following contact with the chain reading lever and Will not be controlled thereby.

The present invention has been described in detail above for purposes of illustration only and is not intended to be limited by this description or otherwise except as defined in the appended claims.

I claim:

1. In a circular knitting machine having drive means and a main drive shaft that extends laterally for connection with said drive means, means for connecting the drive means to drive said shaft and alternatively operable for hand cranking of said shaft, said connecting means comprising a gear train unit having components disposed concentrically on said shaft and components positioned radially with respect thereto, latch means normally holding said radial components at a fixed operating position with respect to said shaft, and said latch means being releasable to allow said radial components to be revolved about said shaft.

2. In a circular knitting machine, connecting means according to claim 1 and characterized further in that said gear train unit has a handle portion extending radially outward therefrom and manually engageable for revolving the gear train unit to hand crank the shaft.

3. In a circular knitting machine, connecting means according to claim 1 and characterized further in that said gear train unit has a crank arm extending radially outward therefrom and carrying a handle manually engageable for revolving said gear train unit to hand crank the shaft, said crank arm and handle being disposed substantially within the axial extent of said gear train unit.

4. In a circular knitting machine, connecting means according to claim 1 and characterized further by stop means carried by said gear train unit and engageable with the gear train to stop rotation of the gears with respect to the unit during revolution of the unlatched unit about the shaft, said stopped gears revolving with the unit to rotate the shaft.

5. In a circular knitting machine having a main drive shaft extending laterally for connection with drive means that includes drive pulleys mounted on the shaft for driving the shaft at different speeds, a drive belt for driving the pulleys and a belt shifter for shifting the drive belt from one pulley to another, connecting means for driving said shaft from the drive belt at an optional speed and alternatively operable for hand cranking of said shaft, said connecting means comprising an additional drive pulley mounted on said shaft for rotation with respect thereto, a gear train contained within a housing mounted on the extending end of said shaft with the shaft being rotatable with respect to said housing, said gear train having components disposed concentrically on said shaft and components positioned radially with respect thereto, latch means normally holding said housing at a fixed position with the gear train positioned for operation by said additional drive pulley, said latch means being releasable to allow said housing to be revolved about said shaft, and stop means carried by said housing and engageable with the gear train to stop rotation of the gears with respect to the housing during revolving of said housing so that said gear train will cause said shaft to revolve with the housing.

6. In a circular knitting machine, connecting means according to claim 5 and characterized further in that said gear train housing has a handle portion extending radially outward therefrom substantially within the axial extent of the housing for engagement in manually revolving said housing.

7. In a circular knitting machine, connecting means according to claim 6 and characterized further in that said latch means is incorporated in said handle portion for release of the latch means by manipulation of said handle portion.

8. In a circular knitting machine having a laterally extending main drive shaft on which are mounted drive pulleys for driving the shaft at different speeds by a belt shiftable from one pulley to another by a belt shifter that is controlled by a shifting mechanism actuated by a catch manipulated into engagement with a riciprocating operating block by a chain reading lever responsive to a chain link cam, means for connecting said belt to said shaft to drive said shaft at an optional speed and for retaining said connection during more than one reciprocation of said operating block, said means comprising an additional drive pulley mounted on said shaft for rotation with respect thereto by said belt upon shifting of the belt thereto by said belt shifter, a gear train unit mounted on the extending end of said shaft and operatingly connected to said additional drive pulley, a belt shifter latch manipulated between an inoperative position and a latching position by said chain reading lever with said lever positioning said latch in latching position during response to a chain link cam, said belt shifter latch having means disposed at the additional pulley position of said belt shifter for engagement therewith to retain said shifter thereat when said latch is in latching position and disengageable therefrom when said latch is manipulated to inoperative position.

9. In a circular knitting machine having a laterally extending main drive shaft on which are mounted drive pulleys for driving the shaft at different speeds by a belt shiftable from one pulley to another by a belt shifter that is controlled by a shifting mechanism actuated by a catch manipulated into engagement with a reciprocating operating block by a chain reading lever responsive to a chain link cam, means for retaining said belt shifter in a shifted position during a subsequent return stroke and operating stroke of said operating block when the chain link cam spans more than one reciprocation of said block, said retaining means comprising a belt shifter latch manipulated between an inoperative position and a latching position by said chain reading lever with said lever positioning said latch in latching position during response to said chain link cam, said belt shifter latch having means disposed at the shifted position of said belt shifter for engagement therewith to retain said shifter in its shifted position when said latch is in latching position and disengageable therefrom when said latch is manipulated to inoperative position.

10. In a circular knitting machine, retaining means according to claim 9 and characterized further in that said belt shifter engaging means comprises a notch formed in said latch, and a lug extending from said belt shifter for engagement in said notch when said latch is in latching position.

11. In a circular knitting machine, retaining means according to claim 9 and characterized further in that said chain reading lever rises in response to the chain link cam, and said belt shifter latch is pivotally mounted intermediate its ends with an operating end riding on the underside of the chain reading lever and a latching end extending to the shifted position of said belt shifter and carrying said belt shifter engaging means, rising of said chain reading lever in response to the chain link cam causing pivoting of said latch to lower said latching end and belt shifter engaging means into latching position and subsequent lowering of said chain reading lever causing pivoting of said latch to raise said belt shifter engaging means to inoperative position.

12. In a circular knitting machine, retaining means according to claim 11 and characterized further in that said belt shifter engaging means comprises a notch formed in the underside of said latch and a lug extending from said belt shifter engageable in said notch when said latching end of the latch is in its lowered latching position.

References Cited by the Examiner UNITED STATES PATENTS 1,148,055 7/15 Scott 66-56 1,335,281 3/20 Evans 66--56 2,420,552 5/47 Morrill 74-626 BROUGHTON G. DURHAM, Primary Examiner. 

1. IN A CIRCULAR KNITTING MACHINE HAVING DRIVE MEANS AND A MAIN DRIVE SHAFT THAT EXTENDS LATERALLY FOR CONNECTION WITH SAID DRIVE MEANS, MEANS FOR CONNECTING THE DRIVE MEANS TO DRIVE SAID SHAFT AND ALTERNATIVELY OPERABLE FOR HAND CRANKING OF SAID SHAFT, SAID CONNECTING MEANS COMPRISING A GEAR TRAIN UNIT HAVING COMPONENTS DISPOSED CONCENTRICALLY ON SAID SHAFT AND COMPONENTS POSITIONED RADIALLY WITH RESPECT THERETO, LATCH MEANS NORMALLY HOLDING SAID RADIAL COMPONENTS AT A FIXED OPERARING POSITION WITH RESPECT TO SAID SHAFT, AND SAID LATCH MEANS BEING RELEASABLE TO ALLOW SAID RADIAL COMPONENTS TO BE REVOLVED ABOUT SAID SHAFT. 